Abstract:
Clean tillage was used as the control, and straw mulching, and cover cropping treatments were established in the apricot orchard in Hexi region. The subordinate function method was employed for a comprehensive evaluation of the effects of different soil management practices on soil physicochemical properties, apricot fruit yield and quality. The results showed that compared with clean tillage, both straw mulching and cover cropping treatments showed significant soil cooling effects from May to October, but a heat preservation effect after October, with straw mulching demonstrating superior heat preservation. Both treatments significantly increased soil water content, decreased soil pH value and bulk density, and enhanced the contents of soil organic matter, available phosphorus, and available potassium. The improvement in nutrient content was generally greater in the straw mulching treatment than in cover cropping. Regarding fruit parameters, both straw mulching and cover cropping significantly increased the single fruit weight, yield, soluble solids, and total sugar content of apricot fruits, while reducing titratable acid content. Correlation analysis indicated that fruit yield was negatively correlated with soil pH value, and soluble solids were positively correlated with available phosphorus. Based on the subordinate function, the comprehensive evaluation showed that the benefit ranking of the treatments was straw mulching > cover cropping > clean tillage. In conclusion, both straw mulching and cover cropping treatments effectively improved the soil hydrothermal regime, optimized soil structure, enhanced soil fertility, and ultimately increased apricot yield and quality. Among them, the straw mulching treatment demonstrated the most significant comprehensive benefits for soil improvement and fruit quality enhancement in the short term, making it the preferentially recommended soil management practice for apricot orchards in this region. However, the cover cropping model, being closer to the natural ecosystem, may possess better long-term sustainability.